As an antenna device used in a base station device of a radio communication system such as mobile phones, there exists an antenna device in which an antenna element and a radio unit processing a radio signal transmitted or received by the antenna element are integrated with each other (for example, see Patent Literature 1).
In the antenna device disclosed in Patent Literature 1, an antenna unit (a planar antenna and a radome) is mounted on the upper side of a radio unit (a transceiver unit). On the lower side of the radio unit, a heat sink unit (heat dissipation fins) externally dissipating heat of the radio unit is mounted.